Where do we find oil? In sedimentary rocks originally located between 7500 and 15,000 feet underground, for a long period of time.

We start with organic material (dead plants and animals) that accumulates and then is buried under later layers of silt or mud, underwater.

The layers of organic matter and silt/mud need to be buried underwater and then underground for millions of years.

This rock must then be buried underground between 7,500 and 15,000 feet for a combination of heat and pressure to transform the organic matter to oil molecules.

Below 15,000, underground heat breaks the organic matter (and any oil) into natural gas. Above 7,500 and the rock hasn’t been squeezed and heated enough to break down the organic material into oil.

Normally in nature, organic material is recycled: dead plants, etc. become soil that new plants use.

Even if the organic material accumulates and is buried, it may not be buried deep enough to convert it to oil.

Even if organic material does get buried and converted into oil, it can then become more deeply buried and turned into natural gas.

On top of this, the oil rich sedimentary rock can be pushed upwards, and through a variety of ways, the oil can leak out of the rock.

The rock also has to have a certain amount of porosity, (microscopic holes and cracks) so the oil can flow.

Lastly, the oil-bearing rock has to have a non- porous cap so the oil doesn’t leak out.

So even if geologists do find the right type of rock, it often doesn’t contain any oil, or extremely small amounts.